Therapeutic gas can be delivered to patients, to provide medical benefits. One such therapeutic gas is nitric oxide (NO) gas that, when inhaled, acts to dilate blood vessels in the lungs, improving oxygenation of the blood and reducing pulmonary hypertension. Because of this, nitric oxide can be provided as a therapeutic gas in the inspiratory breathing gases for patients with pulmonary hypertension.
Many of these patients who may benefit from nitric oxide gas receive breathing gas from a breathing circuit affiliated with a ventilator (e.g., constant flow ventilator, variable flow ventilator, high frequency ventilator, bi-level positive airway pressure ventilator or BiPAP ventilator, etc.). To provide nitric oxide to a patient who receives breathing gas from a ventilator, nitric oxide may be injected into the breathing gas flowing in the breathing circuit. This inhaled nitric oxide (iNO) is often provided as a constant concentration, which is provided based on proportional delivery of the NO to the breathing gas.
Although the above provides many benefits, there remains a need for improvements to delivery of therapeutic gas. For example, there remains a need for new techniques to at least address situations such as, but not limited to, disruptions in breathing gas flow systems used in the delivery of therapeutic gases such as nitric oxide.